Neurostimulation is a treatment method utilized for managing the disabilities associated with pain, movement disorders such as Parkinson's Disease (PD), dystonia, and essential tremor, and also a number of psychological disorders such as depression, mood, anxiety, addiction, and obsessive compulsive disorders. Closed-loop neurostimulation systems deliver the stimulation and modify stimulation parameters based on feedback. Closed-loop systems may reduce power consumption of an internal pulse generator (IPG), decreasing the need to recharge a battery, and increasing battery life. Further, closed-loop systems may be more efficacious in improving symptoms associated with the condition being treated.
Traditional closed-loop systems include incorporating sensors in a stimulating electrode and modulating the stimulation applied by the stimulating electrode based on signals detected by the sensors. In addition to sensing signals in a target area, however, other areas may be reflective of abnormal neural activity associated with a disease condition. Further, electrode polarization from stimulation may interfere with the ability to accurately monitor activity at the stimulating electrode.